Eric, This is a really interesting point. Could you elaborate some specific examples perhaps?
ben g > -----Original Message----- > From: Eric Hawthorne [mailto:[EMAIL PROTECTED] > Sent: Sunday, February 01, 2004 7:11 PM > To: [EMAIL PROTECTED] > Subject: Flaw in denial of "group selection" principle in evolution > discovered? > > > Blast from the recent past. > This is pertinent to the previous discussions on evolution > as a special case of emergent-system emergence. > > It was argued that "group selection" effects have been discredited in > evolutionary biology. I counterargued that denying the possibility of > a selection effect at each more-and-more complex system-level in > a multi-layer complex-ordered emergent system (such as ecosystems, > biological species etc) denies the likelihood of spontaneous emergence of > those complex systems at all. > > I think I've found the source of the confusion regarding group selection > effects. It goes like this: > > A species can evolve a "group-benefit" behaviour so long as the > development > of the behaviour does not, on average, reduce the reproductive success > of individuals > that engage in the group-benefit behaviour, and so long as the behaviour > does > confer, on average, a benefit to the reproductive chances of each > individual in > the well-behaving group. > > The key is in how we interpret "average". The question is whether an > individual > organism always acts "in each short-term encounter" in a manner which > maximizes their > chance of survival-to-breeding-age IN THAT ENCOUNTER, or whether it is > possible > for the individual to wager that taking a slight risk now (and > believing or observing that > others will also do so) will lead to a better chance that the individual > will survive ALL > ENCOUNTERS from now up until it breeds. The organism doesn't have to be > smart enough > to believe in this wager. It is sufficient that the wager be on average > beneficial to the > individual.In that case, through repeated trials by multiple > individuals, the behaviour > which is group-adaptive and individually "lifetime-average" adaptive can > evolve. > > BECAUSE THE EVOLVABLE "GOAL" IS NOT SIMPLY TO MAXIMIZE THE > CHANCE OF SURVIVAL OF AN ORGANISM OF THE NEXT SHORT-TERM ENCOUNTER. > THE "GOAL" IS TO MAXIMIZE THE PROBABILITY OF SURVIVAL OF THE SUM TOTAL > OF ALL OF THE ORGANISM'S ENCOUNTERS UP TO WHEN THE ORGANISM REPRODUCES. > > So it is just a time-scale misunderstanding. Group-adaptive behaviours > increase the member's > probability of surviving to reproductive age, even if they slightly > increase the chance of the > indvidual losing some particular encounter. > > True "extreme" altruistic behavior which conveys CERTAINTY of death in a > single encounter > may not fit into this model, but it can be argued as to whether the > altruistic individual "believes" > they are going to die "for certain" in many incidents or not, or whether > they hold out "faint hope" > in which case the argument above could still hold. In any case, true > "certain death" altruistic behaviour > is an extreme anomoly case of group-adaptive behviour. Most > group-adaptive behaviours are > not of that kind, so "extreme, definitely fatal" altruism is not a good > model for them. > > Eric > > > > >